15289
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 15290
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15288
- Möbius Function
- -1
- Radical
- 15289
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 71
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1786
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes that remain prime through 3 iterations of function f(x) = 10x + 9.at n=36A023301
- Chebyshev even-indexed U-polynomials evaluated at sqrt(7)/2.at n=6A030221
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 80 ones.at n=11A031848
- Prime number spiral (clockwise, South spoke).at n=21A054566
- Primes p for which the period of reciprocal 1/p is (p-1)/12.at n=17A056217
- Numbers k such that 97^k - 96^k is a strong pseudoprime.at n=2A062663
- Primes p such that the sum of the digits of p is not prime, but the sum of each digit raised to the 4th power is prime.at n=11A091368
- Main diagonal of triangle A098495.at n=6A098497
- Numerator of Sum_{i=2..n} (-1)^i/(i*phi(i)).at n=8A101992
- Primes for which the weight as defined in A117078 is 11 and the gap as defined in A001223 is 10.at n=19A119596
- Bond series for second parallel moment of hexagonal net.at n=14A120543
- Primes congruent to 24 mod 43.at n=40A142273
- Primes congruent to 14 mod 47.at n=40A142365
- Primes congruent to 1 mod 49.at n=39A142414
- Primes congruent to 25 mod 53.at n=36A142555
- Primes congruent to 8 mod 59.at n=29A142735
- Primes congruent to 39 mod 61.at n=26A142837
- a(n) = 78*n^2 + 1.at n=14A158769
- Primes p such that p*(p-1)/2-5 and p*(p-1)/2+5 are also prime numbers.at n=32A164623
- Primes p such that p^2 divides 2^(2^(p-1)-1) - 1.at n=20A188465